1. Field of Invention
The present invention relates to dielectric well logging.
2. Description of Prior Art
So far as is known to applicants, previous wave propagation well logging techniques which measured resistivity or resistivity and dielectric constant have employed source coils mounted with their longitudinal axis aligned with the longitudinal axis of the sonde. For analytical purposes, these sources were considered axial magnetic dipoles of infinitesmal extent. An axial magnetic dipole was adequate under conditions when a well borehole was small or when the borehole fluids were not very conductive. Where borehole fluids were conductive, however, eddy currents flowed in the borehole and caused significant signal reduction, so that signal amplitudes were low and variable. Low and variable signal amplitude caused inconsistency in log results, termed poor "repeats", and could in some cases result in a complete loss of information.